Under a massive tower carrying high-tension power lines sits a Japanese Zen garden with glowing lamps hanging from trees. But the night air isn't still -- it's alive with spinning colored lights and dry ice, reverberating with throbbing drumbeats and the remarkable freestyle vocalizations of MC Millennium Collaborator. Drum 'n' bass emerged from Britain several years ago as yet another twig on the family tree of techno-dance music, but by now the skittery, jittery sound has established itself as the most potent form of dance music all over the globe. Employing dizzying ricochets of spasmodic percussion -- imagine a drum-beating toy monkey hurtling down a steep flight of stairs -- the dense rhythms eventually open up to showcase an awesome array of sound effects, real instruments like guitars and horns, sampled percussion, and more. At Respectable Street in West Palm Beach, a troika of young DJs (Blacki, Phat Phil, and Pan) spins drum 'n' bass and tech-step (another hi-NRG form of electronic disco music) from 11 p.m. till the wee hours, finding favor with an expanding clientele. You'd be hard-pressed to find such an invigorating scene in such an improbable location anywhere.